Corrugated cardboard cartons used in the fruit packing industry, commonly referred to as bliss boxes, have stacking tabs on each carton top. These tabs aid in the stacking process by fitting into corresponding slots in the bottom of the carton placed upon it. The cartons are stacked on pallets (palletized) typically three (3) cartons wide, two (2) cartons deep, and up to twelve (12) cartons high. On each carton layer, the top tabs are inserted into the bottom slots to interlock the cartons on top of one another.
Due to storage limitations and transportation restrictions, fruit packers often find it necessary to stack palletized corrugated cardboard cartons three (3) pallets high in cold storage or high humidity environments. Corrugated cardboard boxes do not react well in such environments and most efforts to improve corrugated box performance have not been successful.
When stacking palletized corrugated cardboard cartons on top of one another, load failure often occurs when one carton is dislodged or collapses. Furthermore, during shipping, vibration and load shifting can easily cause a carton to dislodge or collapse and cause other palletized cartons above it to fall. In both situations, the contents of the cartons are often damaged or destroyed.
There are at least three inherent weaknesses with the present corrugated cardboard carton stacking system. First, the stacking tabs of the top layer of cartons are not inserted into any slots. These tabs are left unconnected and are often crushed by the pallet that is placed on top of the top carton layer. A carton with crushed stacking tabs cannot be reused as its tabs will not properly interlock with the bottom slots of a carton placed above it. Second, while the bottom layer of cartons all rest on the pallet and thus are held together on this commonly shared surface, the top layer of cartons are not interconnected. Each stack of cartons resembles a stack of blocks that can easily topple or fall. Third, if a second pallet is stacked on top of the first palletized group of cartons, there is no edge protection for the top layer of cartons upon which the second pallet is placed. If the second pallet should contact the edges of the top layer of cartons during stacking with a sufficient force, the carton edges and sides are typically damaged. Because corrugated cardboard cartons rely on their edges and sides for a majority of their structural strength, once damaged the cartons are incapable of supporting one or more palletized loads.
My invention solves the above problems. Its many objects include providing edge protection, load containment, and the ability to stack palletized units of boxed product while not damaging the special stacking tabs inherent in a corrugated cardboard box design. Another object of my invention is to provide a flat even surface for the next palletized load to be stacked upon. Furthermore, my invention is reusable from palletized load to palletized load.